Products
Beta-carotene is commercially available as a monopreparation mainly in the form of capsules.
Structure and properties
Beta-carotene (C40H56, Mr = 536.9 g/mol) exists as a brown-red crystalline powder that is practically insoluble in water. The lipophilic substance is sensitive to air, light and heat, especially in solution. The carotenoid, which is made up of isoprene units, is found in many fruits and vegetables, for example in carrots, in raw palm oil, in tomatoes, in pumpkin, in spinach, in mangoes, sweet potatoes and apricots. Beta-carotene is a prodrug (precursor) of vitamin A. One molecule of beta-carotene can be cleaved into two molecules of retinal, primarily in the small intestine, but also in the liver and other organs, by an oxidative opening of the double bond. However, this enzymatic formation of vitamin A only takes place when the organism needs vitamin A, i.e. especially in the case of vitamin A deficiency. Therefore, taking beta-carotene does not lead to hypervitaminosis A.
Effects
Beta-carotene (ATC D02BB01) has antioxidant properties. It acts as a free radical scavenger, protecting the skin from the negative effects of solar radiation and reducing its sensitivity to radiation. However, beta-carotene does not prevent sunburn. It is an important precursor and source of vitamin A (see there).
Indications for use
- For the prevention and treatment of vitamin A deficiency symptoms.
- For the prevention of “sun allergy” (polymorphous light dermatosis).
- Erythropoietic protoporphyria
- Pigmentary disorders: Vitiligo or hyperpigmentation
- As a dye for food, drugs and cosmetics.
- As a dietary supplement
Dosage
According to the professional information. Dosage and intake depends on the preparation and indication.
Contraindications
- Hypersensitivity
- Combination with vitamin A preparations or retinoids.
- Hypervitaminosis A
- Severe renal insufficiency
- Liver damage
- High daily dose of over 20 mg in heavy smokers (> 20 cigarettes per day) over a long period of time.
Full precautions can be found in the drug label.
Interactions
Beta-carotene should not be combined with vitamin A preparations or retinoids.
Adverse effects
Possible adverse effects include brownish-yellow skin discoloration at high doses (especially on the face, hands, and feet), yellowing of the stool, and stool irregularities. Taking high daily doses of more than 20 mg of beta-carotene increases the risk of cancer in heavy smokers. Hypervitaminosis A is not possible with beta-carotene because the body does not convert it to vitamin A indefinitely (see above).
